Derivative Financial Instruments (Schedule of Company's Derivative Instruments on Other Comprehensive Income and the Consolidated Statement of Operations) (Details) - Cash Flow Hedges - Designated as Hedging Instrument - Foreign currency forward contracts - USD ($) $ in Thousands		3 Months Ended
		Apr. 01, 2018	Apr. 02, 2017
Derivative Instruments, Gain (Loss) [Line Items]
Gains (Losses) Recognized in OCI - Effective Portion		$ (1,500)	$ (117)
Gains (Losses) Reclassified from OCI into Income - Effective Portion	[1]	(2,192)	1,580
Net revenue
Derivative Instruments, Gain (Loss) [Line Items]
Gains (Losses) Reclassified from OCI into Income - Effective Portion	[1]	(2,568)	2,035
Cost of revenue
Derivative Instruments, Gain (Loss) [Line Items]
Gains (Losses) Reclassified from OCI into Income - Effective Portion	[1]	6	(13)
Research and development
Derivative Instruments, Gain (Loss) [Line Items]
Gains (Losses) Reclassified from OCI into Income - Effective Portion	[1]	99	(19)
Sales and marketing
Derivative Instruments, Gain (Loss) [Line Items]
Gains (Losses) Reclassified from OCI into Income - Effective Portion	[1]	230	(364)
General and administrative
Derivative Instruments, Gain (Loss) [Line Items]
Gains (Losses) Reclassified from OCI into Income - Effective Portion	[1]	$ 41	$ (59)

[1] Refer to Note 10, Stockholders' Equity, which summarizes the accumulated other comprehensive income activity related to derivatives.